Cloud Computing: Hacker Lexicon – What Is Homomorphic Encryption?

Grazed from Wired. Author: Editorial Staff.

The problem with encrypting data is that sooner or later, you have to decrypt it. Keep your cloud files cryptographically scrambled using a secret key that only you possess, and it’s likely no hacker will have the codebreaking resources necessary to crack them. But as soon as you want to actually do something with those files—anything from editing a word document or querying a database of financial data—you have to unlock the data and leave it vulnerable. Homomorphic encryption, a still-mostly-theoretical advancement in the science of keeping secrets, could change that.

A homomorphic encryption scheme is a crypto system that allows computations to be performed on data without decrypting it. A homomorphically encrypted search engine, for instance, could take in encrypted search terms and compare them with an encrypted index of the web. Or a homomorphically encrypted financial database stored in the cloud would allow users to ask how much money an employee earned in the second quarter of 2013…

But it would accept an encrypted employee name and output an encrypted answer, avoiding the privacy problems that usually plague online services that deal with such sensitive data…

Read more from the source @ http://www.wired.com/2014/11/hacker-lexicon-homomorphic-encryption/